That cheap junk is almost entirely destroyed by chlorine within a couple days. It's nothing but a placebo.
Maybe so, do you have any chemical kinetic data on the rate of reaction with hypochlorite you can point me to? I know from other use in a non-pool case that quats are excellent algaecides, and are quite stable. However, I have had no algae problems since I began using it 9 years ago, and as you say it is cheap, so I am happy with using it.
I think the point is that use of an algaecide is not a requirement if following the TFP methodology. How each individual manages their pool is their choice. Similar to you where our pools are open year round, I have not used any algaecide and have not had any algae in over 7 years. I just follow the FC/CYA Levels recommendations, and test regularly.
As I said, I have followed the TFP system, but I add the extra precaution of the algaecide. Now perhaps I don't need to but it is the least inexpensive chemical that I put into the pool, ($25 bottle of concentrate lasts 2 years) and causes no other problems, so to me it is worth it. Admittedly I have not run the control without it, but I don't want to take that risk and then possibly have to deal with algae again. I have a lot of leaves year round due to the Coastal Live Oaks that surround the pool which probably caused the annual algae problems I had when we first bought the place when I had a pool maintenance service and they merely dosed it with chlorine which provided only a temporary fix. I was simply giving my experience to the person who was having the algae problem. I agree everyone has to manage their own pool to their own satisfaction.
It's your job to prove that what you are suggesting has merit. Perhaps start another post on the topic rather than taking this thread further off topic.
PolyQuat-60 is a quaternary ammonium based algaecide (think of it like non-alcohol based hand sanitizer). It will help to keep algae at bay and it is less sensitive to chlorine oxidation than the cheaper linear quat algaecides. It does break down over time so it has to be replenished if used regularly but the by-products are harmless and don’t mess with your pool.
www.troublefreepool.com
It is certainly not off topic ("algae, chemistry problem"). Algaecide kills algae, that is fact. You mentioned the rapid destruction of the quat by chlorine, which is a chemical reaction (which may have been taking the thread off topic initially) Not having heard this before, I merely asked for the source of the information. Since you made the statement, surely it is up to you to provide scientific proof of its veracity. If you are not able to, it is just worthless anecdote.
False.
Oh, I'm sorry, must have missed your scientific proof backing up your recommendation to use it. You said that using it "really helps" and has "no adverse effects", but the link to your scientific proof seems to have disappeared. Could you re-post that?
No, it's not. My job is to warn a brand new person when they are getting poor advice from someone with nothing to back up their suggestion. Thankfully the mods have kindly taken care of that.
Thank you for your reply. So the difference between PQ-60 and the linear quats is the rate of breakdown by chlorine? They are both quaternary ammonium salts, and both are effective algaecides with similar killing power. Your analogy with hand-sanitizers is inaccurate in this regard. "Less sensitive" is a rather general statement, which doesn't mean much to a trained scientist. Are there studies on this with real numbers that you can point me to? Maybe I will switch to PQ-60. It's only a few dollars more expensive anyway.PolyQuat-60 is a quaternary ammonium based algaecide (think of it like non-alcohol based hand sanitizer). It will help to keep algae at bay and it is less sensitive to chlorine oxidation than the cheaper linear quat algaecides. It does break down over time so it has to be replenished if used regularly but the by-products are harmless and don’t mess with your pool.
Algaecide - Further Reading
So you are now saying algaecide doesn't kill algae? All the other scientific evidence is incorrect?
The true originator of the FC and CYA relationship was Ben Powell. Richard Falk (Chem Geek) then determined the FC/CYA ratio rules after that (Pool Water Chemistry). Richard had many back and forths on PolyQuat 60 with the manufacturer...one below talks about frequency of use based on breakdown. I have never seen any posts with any chemistry on the breakdown from Richard. Here is his note on the breakdown and frequency of use. Interestingly, he indicates the same thing that we (TFP) and @Donldson are trying to convey...Algaecide is unnecessary if one maintains the proper Free Chlorine (FC) level for the Cyanuric Acid (CYA) level.
www.troublefreepool.com
Thank you for your helpful response.The true originator of the FC and CYA relationship was Ben Powell. Richard Falk (Chem Geek) then determined the FC/CYA ratio rules after that. Richard had many back and forths on PolyQuat 60 with the manufacturer...one below talks about frequency of use based on breakdown. I have never seen any posts with any chemistry on the breakdown from Richard. Here is his note on the breakdown and frequency of use.
polyquat?
Hi, I heard that if algaecide is to be used polyquat is the one to use. Are there any disadvantages or possible health hazards from it? Does it stay in the water for good, break down into something bad or go away? What do you guys think of the Kem-Tek KTK-50-0006 Pool and Spa 60-Percent...
There's 100's/1000's of threads on TFP of people using algaecide when they already have algae
Yes, you are correct. I said so in an earlier post, where I pointed out that I have not run the control without algaecide and my reasons.
But you are not me, and as I say above, I would rather not and risk the possibliity, however slight, of another algal bloom and the subsequent work to get rid of it. I had enough of that during the pool service years, but none since I have been following my protocol (which as you can see from my info was 9 years ago and including a big hurricane!). It can't be any better as I have a clear pool now (being able to see the philips head screws on the drain cap and which way up a coin is!). Just adding 2 oz of the liquid a few times during the season is fine by me. And the cost is very minimal even compared to the other minimal ongoing costs I incur for NaCl, HCl, CYA and electricity.
Algecides *inhibit* algae growth. They can't stop the exponential runaway train, and that's a huge difference. If it killed active blooms, all anyone with a swamp would need was algecide.
So I'm still not quite clear... are you by chance a scientist?
Then the opposition to you offering advice based entirely upon anecdotal evidence should be pretty obvious, yes? You seem to be holding everyone else to a higher standard than you expect to be held to, why is that?
